package com.itheima.reggie.controller;

import com.aliyun.oss.OSS;
import com.aliyun.oss.OSSClientBuilder;
import com.aliyun.oss.model.PutObjectRequest;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.InputStream;
import java.util.UUID;

/**
 * 文件上传和下载
 */
@RestController
@RequestMapping("/common")
@Slf4j
public class CommonController {

    @Value("${reggie.oss.endpoint}")
    private String endpoint;

    @Value("${reggie.oss.accessKeyId}")
    private String accessKeyId;

    @Value("${reggie.oss.accessKeySecret}")
    private String accessKeySecret;

    @Value("${reggie.oss.bucketName}")
    private String bucketName;

    /**
     * 文件上传
     * @param file
     * @return
     */
    @PostMapping("/upload")
    public R<String> upload(MultipartFile file){
        //file是一个临时文件，需要转存到指定位置，否则本次请求完成后临时文件会删除
        log.info(file.toString());

        //原始文件名
        String originalFilename = file.getOriginalFilename(); // abc.jpg
        String suffix = originalFilename.substring(originalFilename.lastIndexOf("."));

        //使用UUID重新生成文件名，防止文件名称重复造成文件覆盖
        String fileName = UUID.randomUUID().toString() + suffix; // dfsdfdfd.jpg

        // 创建OSSClient实例
        OSS ossClient = new OSSClientBuilder().build(endpoint, accessKeyId, accessKeySecret);

        try {
            // 将文件上传到OSS
            InputStream inputStream = file.getInputStream();
            ossClient.putObject(new PutObjectRequest(bucketName, fileName, inputStream));
        } catch (IOException e) {
            e.printStackTrace();
            return R.error("文件上传失败");
        } finally {
            if (ossClient != null) {
                ossClient.shutdown();
            }
        }

        return R.success(fileName);
    }

    /**
     * 文件下载
     * @param name
     * @param response
     */
    @GetMapping("/download")
    public void download(String name, HttpServletResponse response){
        // 创建OSSClient实例
        OSS ossClient = new OSSClientBuilder().build(endpoint, accessKeyId, accessKeySecret);

        try {
            // 获取OSS文件流
            InputStream objectContent = ossClient.getObject(bucketName, name).getObjectContent();

            // 输出流，通过输出流将文件写回浏览器
            ServletOutputStream outputStream = response.getOutputStream();

            response.setContentType("image/jpeg");

            int len = 0;
            byte[] bytes = new byte[1024];
            while ((len = objectContent.read(bytes)) != -1){
                outputStream.write(bytes, 0, len);
                outputStream.flush();
            }

            // 关闭资源
            outputStream.close();
            objectContent.close();
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            if (ossClient != null) {
                ossClient.shutdown();
            }
        }
    }
}